The present invention relates to the amelioration of the bad taste of dental etching compositions by incorporating a flavor formulation into them that improves their taste.
In dentistry, it is sometimes necessary to etch the enamel or dentin surfaces of the teeth with an acid etch, particularly to increase the bonding of a subsequently applied coating to those surfaces. In addition to cleaning those surfaces, the etching also creates micropores and thereby roughens them and increases the mechanical bonding for strength of the coating to be subsequently applied to the roughened surfaces. Generally, the dental etching compositions also contain a gelling agent, the purpose of which is to help the dental etching compositions adhere to the enamel, thereby making the etching composition more effective. Commercially available dental etching gels contain phosphoric acid as the active ingredient. The major problem with currently commercially available dental etching gels, however, is that they have a bad taste. This is particularly a problem where the etches are used on the teeth of children, whose taste buds are particularly acute. Therefore, there is a definite need for a better tasting dental gel that would be more palatable to both young and old alike.
A number of patents mention dental etches, but none of them recognizes the bad taste of the etches, let alone addresses the bad taste and offers a solution to improve the taste. These patents are: U.S. Pat. Nos. 4,376,673; 5,766,012; 5,385,728; 5,256,065 and 5,061,183.
It is understood that one commercially available dental etch comprises water, ethanol, polyglycol, H3PO4, silica and colorants.
It has now been found that it is possible to improve the taste of dental etching gels by incorporation of a flavoring formulation either into the commercially available dental etching gels or as part of an overall formulation of the dental gel, including the flavoring formulation of the invention.
It is an object of the present invention to provide a flavoring formulation to improve the bad taste of dental etching gels.
It is an object of the present invention to provide a flavoring formulation that may be incorporated into currently commercially available dental etching gels in order to improve the taste of those dental gels.
It is another object of the present invention to provide a total etching gel that includes the flavoring formulation of the invention in an overall product that has a much better taste than the currently commercially available dental etching gels.
These objects, as well as further objects which will become apparent from the discussion that follows, are achieved, in accordance with the present invention, by an acid dental etch having improved taste, which comprises:
(a) an acid that is effective in etching tooth surfaces in an amount effective to etch a surface of a tooth;
(b) a flavoring formulation that improves the flavor of the dental etch and is stable in the acid, in an amount that is effective in improving the flavor of the dental etch.
The acid is preferably phosphoric acid, which may be present in the etch in an amount of from about 10% to about 40% by weight of the gel. The flavoring formulation comprises a flavoring agent. Examples of flavoring agents are bubble gum flavor, cherry flavor, grape flavor, anise oil, cassia oil, vanilla extract, vanilla creme, orange flavor, anethole, licorice, and spearmint oil. The flavoring formulation may also comprise a sweetener. Examples of suitable sweeteners are neohespiridin dehydrochalcone, xylitol, and Sucralose.
Preferably, the dental etch in one embodiment of the invention also comprises a sufficient amount of gelling agent to form a gel. In the total acid gel of the invention, the gelling agent may be comprised of sodium alginate, a sequestrant, and a source of calcium. Preferably, the sequestrant is sodium citrate. The source of calcium may be dicalcium phosphate. In another embodiment of the invention, the gelling agent may be silica.
The acid dental etching gel composition having improved taste comprises an acid in an amount effective to etch the enamel or dentin of a tooth; a flavoring formulation that improves the flavor of the dental etching gel composition and is stable in the acid, in an amount that is effective in improving the flavor of the dental etch; and sufficient gelling agent to form a gel.
Preferably, the acid is phosphoric acid. The acid may be present in the etch in an amount of from about 10% to about 40% by weight of the gel composition. Preferably, the acid is present in the etch in an amount of at least about 25% by weight of the gel composition. More preferably, the acid is present in the etch in an amount of from about 30% to about 40% by weight of the gel composition. The usual formulation contains about 35% of the acid by weight of the gel composition.
The flavoring formulation comprises a flavoring agent. Preferably, the flavoring agent is selected from the group consisting of a bubble gum flavor, a cherry flavor, grape flavor, anise oil, cassia oil, vanilla extract, vanilla creme, orange flavor, anethole, licorice, spearmint oil, phenylacetaldehyde diisobutyl acetal, and mixtures thereof. Children prefer bubblegum, grape and strawberry flavors. Adults prefer mint and vanilla flavors. The amount of the flavoring agent is from about 5 percent to about 25 percent.
The flavoring formulation may also comprise a sweetener. Preferably, the sweetener is selected from the group consisting of neohespiridin dehydrochalcone, xylitol, Sucralose, and mixtures thereof. An effective amount of the sweetener is used, e.g., from about 0.5 percent to about 50 percent.
In one embodiment of the invention, the gelling agent may be comprised of sodium alginate, a sequestrant, and a source of calcium. Preferably, the sequestrant is sodium citrate. Preferably, the source of calcium is dicalcium phosphate. An effective amount of sodium alginate is from about 1 percent to about 5 percent. The effective amount of sequestrant is preferably from about 0.5 percent to about 3 percent. The amount of the source of calcium is from about 0.05 percent to about 2 percent.
When a sodium alginate, e.g., Keltone HV, is used, it requires a cross-linking agent, e.g., a calcium salt, and a sequestrant in order to properly gel. However, when an alkylene glycol alginate is used, neither a calcium salt nor a sequestrant is required in order to gel. The alkylene group may contain from 2 to about 6 carbon atoms. The alkylene glycol alginate should be non-toxic. Preferred is from about 1 to about 15 percent of proylene glycol alginate, which is commercially available as Kelcoloid HVF. When using Kelcoloid HVF, it is preferred to hydrate it first and then add the flavoring agent and the acid etching compound. The gelling agent is stable in the low pH environment caused by the acid etching compound.
In another embodiment of the invention, the gelling agent may be comprised of silica in an amount of from about 4% to about 18% of the total formulation. Preferably, the silica is present in an amount of from about 4.5% to about 7% of the total formulation. Most preferably, the silica is present in an amount of about 5%. Generally, the smaller particle sizes are preferred. A minimum of 200 screen size is preferred.
In this embodiment of the invention, water, ethanol, polyglycol and colorants may also be present in the formulation:
Water may be present in an amount of from about 20% to about 45% of the total formulation. Preferably, water is present in an amount of from about 23% to about 34% of the total formulation. Most preferably, water is present in an amount of about 23%.
Ehtanol may be present in an amount of from about 8% to about 14% of the total formulation. Preferably, ethanol is present in an amount of from about 8% to about 11% of the total formulation. Most preferably, ethanol is present in an amount of about 9%.
Polyglycol may be present in an amount of from about 3% to about 5% of the total formulation. Preferably, polyglycol is present in an amount of from about 3% to about 4% of the total formulation. Most preferably, polyglycol is present in an amount of from about 3% to about 3.5% of the total formulation.
Colorant may be present in an amount of from about 0.005% to about 0.15% of the total formulation. Preferably, colorant is present in an amount of from about 0.005% to about 0.01% of the total formulation. Most preferably, colorant is present in an amount of about 0.006%. Illustrative of colorants that may be used are FDandC Blue, titanium dioxide, turmeric yellow, and the like.
The following Examples provide samples of the preferred embodiments of the invention.